Microscope stage

ABSTRACT

The invention contemplates a microscope including a stage for supporting a slide for selective positioning in liquid-immersed contact with part of an optical system, such as a fieldilluminating condenser element. The arrangement is such that the plane of liquid contact is offset from the adjacent plane of the stage platform and so that selective positioning of the slide cannot result in liquid contact with the stage or with any slidesupporting element.

[ Oct. 16, 1973 United States Patent [191 Burboeck [5 MICROSCOPE STAGE198,607 12/1877 Gundlach................... 21 07 l 1 79 G dl [75]Inventor: gajns Peter Burboeck,Morr1s Plains, 32 4 3 z ss [73] Assignee:Carl Zeiss-Stiftung, Primary Examiner-David H. Rubin Attorney-Nichol M.Sandoe et a1.

Oberkochen/Wuerttemberg, Germany [57] ABSTRACT The inventioncontemplates a microsco [22] Filed: Apr. 10, 1972 v r element. Thearrangement is such that the plane of liquid contact is offset from theadjacent plane of the pe including a stage for supporting a slide forselective positioning in liquid-immersed contact with part of an opticalsystem, such as a field-illuminating condense 76 002 1 52 0 mm 0 m 4 3m" 2 "m 4 2 l 1 G w s A U1 1 11] .l 21 2 55 .l.

stage plat- [58] Field of Search.......................... 350/86, 87,90

form and so that selective positioning of the slide cannot result inliquid contact with the sta slide-supporting element.

ge or with any [56] References Cited UNITED STATES PATENTS 2,003,3876/1935 350/90 X 9 Claims, 3 Drawing Figures MICROSCOPE STAGE Thisinvention relates to a microscope construction and in particular to astage for supporting and selectively positioning a microscope slide inliquidimmersion contact with an adjacent optical surface, such as a flatilluminating-condenser surface.

In the traditional fabrication of microscopes of the characterindicated, the microscope slide is supported directly on a stageplatform, and selectively operable positioning means determines thedisplacement of the slide on the platform, to the end that a selectedarea of the slide is placed in the field of the microscope. In aliquid-immersed optical coupling to such a slide, liquid is necessarilysmeared over the slide and the liquid will wet the stage platform ifthere is a sufficient manipulative displacement of the slide. For slideswhich have multiple specimens at locales spaced to an extent approachingthe span of the stage opening for such optical means, it is unavoidablethat immersion liquid will wet the stage. Such wetting accumulates,dries to the point of stickiness, attracts contaminating foreign matterand in general interferes with the overall use of the instrument.

Procedures for periodic cleaning are necessary, and technicians have hadto accept such procedures as a fact of life.

It is an object of the invention to provide an improved construction ofthe character indicated, wherein such procedures are materially, if nottotally rendered unnecessary.

Another object is to provide an improved microscope stage constructionwherein immersion-liquid wetting of stage parts is inherently avoidable.

A specific object is to achieve the above objects in a stage whichaccommodates a microscope slide with a useful specimen area having spanequal to or exceeding half the span of the stage-platform opening whichaccommodates the optical element which is liquidimmersion coupled to theslide.

Other objects and various further features of novelty and invention willbe pointed out or will occur to those skilled in the art from a readingof the following specification in conjunction with the accompanyingdrawings. In said drawings, which show, for illustrative purposes only,a preferred form of the invention:

FIG. 1 is a perspective view of the stage and adjacent parts of amicroscope of the invention;

FIG. 2 is a simplified, enlarged sectional view taken at 22 in FIG. 1;and

FIG. 3 is a similar sectional view, taken at 33 in FIG. 2.

The drawings show a stage of the invention as embodied in a microscopehaving frame-based viewingobjective and illuminating systems 1 1-12 on acommon upstanding optical axis 13, for examining selected regions of aspecimen slide 14. The viewing system 11 is above the specimen slide 14and the illuminating system 12 is below. The stage 10 is built on aframe-based platform 15 having a central circular opening 16 (ofdiameter D which accommodates an upwardly projecting element 17 of theilluminating system; system 17 terminates in a condenser lens having anupwardly facing flat optical surface 18, closely adjacent the undersideof slide 14. A drop of liquid, such as a suitable oil, placed on surface18 is the means of direct optical transmission of light to the body ofslide 14, at the local region of interest, thus establishing aliquid-immersion coupling to the slide.

In accordance with the invention, theslide 14 is so supported that theimmersion liquid which necessarily wets the underside of slide 14 cannotbe drawn into contact with any part of the stage, in spite of a largerange of manipulative positioning of slide 14, in the course ofcompleting an examination of the total possible specimen area'of theslide. This is accomplished through the employment of an auxiliary stageor flat plate 19, of thickness substantially exceeding the relativelysmall physical clearance through which liquidimmersed optical couplingis established; plate 19 has a large central opening, of length L justshort of that of the microscope-slide 14. Plate 19 may for example be ofmetal, 2mm thick, and is slidable on the upper surface of platform 15.

Stage 10 is shown with selective positioning means comprising twomanually operable orthogonally related, rectilinearly guided drives forplate 19. A first or main slide comprises an arm 20, secured to a base21. Base 21 has a dovetail-guided relation with an elongate frame member22 secured to a side margin of the stage platform 15. A knob 23 on arm20 drives a pinion (not shown) meshing with a rack 24 secured to member22, thus enabling a Y-axis selective positioning of arm 20. Plate 19 iseffectively a cross slide, having a tongue 25 secured at 26 to nut means27 (see FIG. 3) forming part of second-component positioning means. Nutmeans 27 is in constant threaded engagement with lead-screw means 28journalled in arm 20 and manually operable upon adjustment of a secondknob 29, thus enabling an X-axis selective positioning of plate 19.

To complete the identification of parts, microscopeslide location onplate 19 is achieved by suitable abutments which may all be formed in orcarried by an abutment plate 30, secured to plate 19. Plate 30 is showngenerally L-shaped and is relieved at 31-32 to permit clean andunambiguous slide-margin referencing, at one end to an end abutment 33,and along one side to spaced edge abutments 34-35. A swing ann 36 ispivotally carried at the remote end of plate 30, and the connectionincorporates a residual spring bias, in the clockwise direction, asindicated by legend in FIG. 1; a downward offset 37 in arm 36 brings thesubstantial extent of arm 36 into the plane of plate 30, so that arm 36may have resiliently urged corner contact with slide 14, thus completingthe abutment system of slide retention and location.

The length L of the plate opening, being just short of the length ofslide 14, enables end margin support of the slide on plate 19, andabutment plate 30 is so located on plate 19 as to offset or set back theabutment 33 from the adjacent edge of the opening in plate 19, toestablish such slide support, as will be understood. On the other hand,plate 30 is preferably so secured as to position abutments 34-35 clearof the adjacent longitudinal edge of the opening in plate 19, thusenabling immersion liquid to wet slide 14 all the way to itslongitudinal edge, without exposing the same for wetting contact withplate 19; preferably, the effective width W of the opening of plate 19is so selected as to exceed the width dimension of anticipatedmicroscope-slide sizes, so as to also assure against wetting plate 19 atthe opposite longitudinal edge of its opening. As a further precaution,anticipating such accidental or careless removal of a wetted slide 14 asto cause immersion liquid to catch on one of the longitudinal ends ofthe opening in plate 19, I show in FIG. 2 a preference that these edgesbe relieved along the bottom surface of plate 19, as indicated at 36-37.

As a further feature of the invention, each of the orthogonally relatedpositioning systems includes limiting abutments or stops whereby the Xand Y components of displacement are only permitted over a particularlimiting range. FIG. 1 will be understood to provide a schematic showingof such abutment means for X- displacement of plate 19, at limits 40-41,and for Y- displacement of plate 19, at limits 42-43. Such abutmentmeans are contained within arm 20, for the X range of positioningadjustment, and within base 21, for

the Y range of positioning adjustment. In both cases, the limiting means(40-41; 42-43) are selected with reference to the relation between (a)the effective diameter D of the upwardly projecting element 17 of theilluminating system and (b) the particular effective span (L or W) ofinterest in the opening of plate 19. Thus, in the rectilinearX-positioning range between limits 40-41, the operative positions ofthese limits are so selected that therectilinear center of the openingof plate 19 (i.e., mid-point of the span L) is movable only (i.e., atleast no more than) a first predetermined distance on each side of theoptical axis 13, said amount being less than one half'the differencebetween the rectilinear extent'L of the plate opening and the effectivediameter D of the optical element; in the rectilinear Y-positioningrange between limits 42-43, the operative positions of these limits areso selected that the rectilinear center of the opening of plate 19(i.e., midpoint of the span .W) is movable only (i.e., at least no morethan) a second predetermined distance on each side of the optical axis13, said amount being less than one half the difference between therectilinear extent W of the plate opening and the effective diameter D,of the optical element.

With structure as described, and with the respective rectilinear L and Wmargins of the plate opening parallel to the respective orthogonalpositioning guide systems, the slide 14 may present a relatively largespecimen area (or area of plural specimens) for successive examination,using the same liquid-immersion coupling throughout the examination,even to the marginal limits of displacement (40-41, 42-43). Slide wettedareas never contact any of the stage structure. Immersion liquid thusstays clean and uncontaminated, and so also does the stage structure. Itis thus feasible to affix a selflubricating bearing surface to theunderside of plate 19,

as suggested by the spaced longitudinally aligned areas 45-46, withoutcontamination of these areas with immersion liquid or foreign matterentrained thereby; a coating or adhered film of polytetrafluoroethyleneis preferred at each of the areas 45-46.

The described device will be seen to have achieved all stated objects,assuring cleaner maintenance of the instrument and simplifiedprocedures.

While the invention has been described in detail for the preferred formshown, it will be understood that modifications may be made withoutdeparture from the invention.

What is claimed is:

1. In a microscope, a frame, a stage comprising a platform having a flatupper surface and carried by said frame, said platform having a centralopening,-optical means carried by said frame beneath said stage andincluding an element on an axis projecting upwardly through said openingand to an elevation above said upper surface, said element including aflat optical surface at an elevation ofi'set above said upper surface ofsaid platform, slide-holder means including a flat plate slidable on theupper surface of said platform, said plate being centrally open over anarea greater than the central opening of said platform, selectivelyoperable positioning means coacting between said platform and saidslide-holder means for selectively positioning the opening of said platewith respect to the axis of said projecting element, said slide-holdermeans including margin-locating abutment means for a specimen slidecarried by said plate, said abutment means comprising at least twogenerally opposed abutment elements which are set back from the adjacentedge of the open area of said plate, whereby the specimen area oftranslucent specimen slide may be supported by and located on said platein the span between said generally opposed abutments, said opticalsurface being in such close adjacency to the plane of the upper surfaceof said plate that said optical surface and the underside of themicroscope slide maybe in liquid-immersed contact, the thickness of saidplate substantially exceeding the axial offset of said optical flatsurface from the slide-supporting surface of said plate, saidpositioning a means including a rectilinear-guide and margin-limitingabutment means limiting the range of displacement of the rectilinearcenter of said plate within a predetermined amount on each side of theoptical axis, said amount being less than one half the differencebetween the rectilinear extent of the plate opening and the rectilinearextent of the optical surface, all said rectilinear quantities beingtaken along an axis in the plane of microscope-slide support and throughthe optical axis, whereby immersion liquid is kept from contact withsaid plate at even the marginal limits of operation of said positioningmeans.

2. A microscope according to claim 1, in which said positioning meanscomprises two orthogonally related positioning systems for selectivetwo-component positioning of the microscope slide with respect to saidoptical surface.

3. A microscope according to claim 2, in which said optical element iscircular at the plane of the optical surface, and in which said plateopening is generally rectangular with sides parallel to the respectiveorthogonally related positioning systems.

4. A microscope according to claim 3, in which each positioning systemincludes a rectilinear guide and abutment means limiting the range ofdisplacement of the rectilinear center of the opening of said plate to apredetermined amount on each side of the optical axis, said amountbeingless than one half the difference between the rectilinear extent ofthe plate opening and the effective diameter of said optical element,the rectilinear quantities for one positioning system being takenparallel to the axis of one of the orthogonal guides and the rectilinearquantities for the other positioning system being taken parallel to theaxis of the other orthogonal guide.

5. A microscope according to claim l,'in which the underside of saidplate is marginally relieved.

6. A microscope according to claim 1, in which said optical means ispart of a stage illuminator.

7. In a microscope, a frame, a stage comprising a platform having a flatupper surface and carried by said frame, said platform having a centralopening, optical means carried by said frame beneath said stage andincluding an element on an axis projecting upwardly through said openingand to an elevation above said upper surface, said element including aflat optical surface at an elevation offset above said upper surface ofsaid platform, slide-holder means including a flat plate carrying alayer of self-lubricating material on its lower surface and slidable onthe upper surface of said platform, said plate being centrally open overan area greater than the central opening of said platform, selectivelyoperable positioning means coacting between said platform and saidslide-holder means for selectively positioning the opening of said platewith respect to the axis of said projecting element, said slide-holdermeans including margin-locating abutment means for a specimen slidecarried by said plate, said abutment means comprising at least twogenerally opposed abutment elements which are set back from the adjacentedge of the open area of said plate, whereby the specimen area of atranslucent specimen slide may be supported by and located on said platein the span between said generally opposed abutments, said opticalsurface being in such close adjacency to the plane of the upper surfaceof said plate that said optical surface and the underside of themicroscope slide may be in liquidimmersed contact, and margin-limitingmeans operative to confine positioning movement of said slideholdermeans to an extent that said optical means can never contact any part ofthe edge of the centrally open area of said plate, whereby immersionliquid may be in continuous contact with any specimen-slide area ofcurrently positioned interest to permit specimen scanning without dangerof immersion-liquid contact with said plate or with the self-lubricatinglayer.

8. The microscope of claim 7, in which said selflubricating layerincludes polytetrafluoroethylene.

9. In a microscope, a frame, a stage comprising a platform having a flatupper surface and carried by said frame, said platform having a centralopening, optical means carried by said frame beneath said stage andincluding an element on an axis projecting upwardly through said openingand to an elevation above said upper surface, said element including aflat optical surface at an elevation offset above said upper surface ofsaid platform; and a unit-handling slide-holder assembly including aflat slide-holder plate slidable on the upper surface of said platform,said plate being centrally open over an area greater than the centralopening of said platform, selectively operable positioning meansincluding a mounting element securable to a part carried by saidplatform and coacting between said platform and said slide-holder platefor selectively positioning the opening of said plate with respect tothe axis of said projecting element, said slide-holder means includingmargin-locating abutment means for a specimen slide carried by saidplate, said abutment means comprising at least two generally opposedabutment elements which are set back from the adjacent edge of the openarea of said plate, whereby the specimen area of a translucent specimenslide may be supported by and located on said plate in the span betweensaid generally opposed abutments, said optical surface being in suchclose adjacency to the plane of the upper surface of said plate thatsaid optical surface and the underside of the microscope slide may be inliquid-immersed contact, and margin-limiting means operative to confinepositioning movement of said slide-holder plate to an extent that saidoptical means can never contact any part of the edge of the centrallyopen area of said plate.

1. In a microscope, a frame, a stage comprising a platform having a flatupper surface and carried by said frame, said platform having a centralopening, optical means carried by said frame beneath said stage andincluding an element on an axis projecting upwardly through said openingand to an elevation above said upper surface, said element including aflat optical surface at an elevation offset above said upper surface ofsaid platform, slide-holder means including a flat plate slidable on theupper surface of said platform, said plate being centrally open over anarea greater than the central opening of said platform, selectivelyoperable positioning means coacting between said platform and saidslide-holder means for selectively positioning the opening of said platewith respect to the axis of said projecting element, said slide-holdermeanS including margin-locating abutment means for a specimen slidecarried by said plate, said abutment means comprising at least twogenerally opposed abutment elements which are set back from the adjacentedge of the open area of said plate, whereby the specimen area oftranslucent specimen slide may be supported by and located on said platein the span between said generally opposed abutments, said opticalsurface being in such close adjacency to the plane of the upper surfaceof said plate that said optical surface and the underside of themicroscope slide may be in liquid-immersed contact, the thickness ofsaid plate substantially exceeding the axial offset of said optical flatsurface from the slidesupporting surface of said plate, said positioningmeans including a rectilinear-guide and margin-limiting abutment meanslimiting the range of displacement of the rectilinear center of saidplate within a predetermined amount on each side of the optical axis,said amount being less than one half the difference between therectilinear extent of the plate opening and the rectilinear extent ofthe optical surface, all said rectilinear quantities being taken alongan axis in the plane of microscopeslide support and through the opticalaxis, whereby immersion liquid is kept from contact with said plate ateven the marginal limits of operation of said positioning means.
 2. Amicroscope according to claim 1, in which said positioning meanscomprises two orthogonally related positioning systems for selectivetwo-component positioning of the microscope slide with respect to saidoptical surface.
 3. A microscope according to claim 2, in which saidoptical element is circular at the plane of the optical surface, and inwhich said plate opening is generally rectangular with sides parallel tothe respective orthogonally related positioning systems.
 4. A microscopeaccording to claim 3, in which each positioning system includes arectilinear guide and abutment means limiting the range of displacementof the rectilinear center of the opening of said plate to apredetermined amount on each side of the optical axis, said amount beingless than one half the difference between the rectilinear extent of theplate opening and the effective diameter of said optical element, therectilinear quantities for one positioning system being taken parallelto the axis of one of the orthogonal guides and the rectilinearquantities for the other positioning system being taken parallel to theaxis of the other orthogonal guide.
 5. A microscope according to claim1, in which the underside of said plate is marginally relieved.
 6. Amicroscope according to claim 1, in which said optical means is part ofa stage illuminator.
 7. In a microscope, a frame, a stage comprising aplatform having a flat upper surface and carried by said frame, saidplatform having a central opening, optical means carried by said framebeneath said stage and including an element on an axis projectingupwardly through said opening and to an elevation above said uppersurface, said element including a flat optical surface at an elevationoffset above said upper surface of said platform, slide-holder meansincluding a flat plate carrying a layer of self-lubricating material onits lower surface and slidable on the upper surface of said platform,said plate being centrally open over an area greater than the centralopening of said platform, selectively operable positioning meanscoacting between said platform and said slide-holder means forselectively positioning the opening of said plate with respect to theaxis of said projecting element, said slide-holder means includingmargin-locating abutment means for a specimen slide carried by saidplate, said abutment means comprising at least two generally opposedabutment elements which are set back from the adjacent edge of the openarea of said plate, whereby the specimen area of a translucent specimenslide may be supported by and located on said plate in the span betweensaid genErally opposed abutments, said optical surface being in suchclose adjacency to the plane of the upper surface of said plate thatsaid optical surface and the underside of the microscope slide may be inliquid-immersed contact, and margin-limiting means operative to confinepositioning movement of said slide-holder means to an extent that saidoptical means can never contact any part of the edge of the centrallyopen area of said plate, whereby immersion liquid may be in continuouscontact with any specimen-slide area of currently positioned interest topermit specimen scanning without danger of immersion-liquid contact withsaid plate or with the self-lubricating layer.
 8. The microscope ofclaim 7, in which said self-lubricating layer includespolytetrafluoroethylene.
 9. In a microscope, a frame, a stage comprisinga platform having a flat upper surface and carried by said frame, saidplatform having a central opening, optical means carried by said framebeneath said stage and including an element on an axis projectingupwardly through said opening and to an elevation above said uppersurface, said element including a flat optical surface at an elevationoffset above said upper surface of said platform; and a unit-handlingslide-holder assembly including a flat slide-holder plate slidable onthe upper surface of said platform, said plate being centrally open overan area greater than the central opening of said platform, selectivelyoperable positioning means including a mounting element securable to apart carried by said platform and coacting between said platform andsaid slide-holder plate for selectively positioning the opening of saidplate with respect to the axis of said projecting element, saidslide-holder means including margin-locating abutment means for aspecimen slide carried by said plate, said abutment means comprising atleast two generally opposed abutment elements which are set back fromthe adjacent edge of the open area of said plate, whereby the specimenarea of a translucent specimen slide may be supported by and located onsaid plate in the span between said generally opposed abutments, saidoptical surface being in such close adjacency to the plane of the uppersurface of said plate that said optical surface and the underside of themicroscope slide may be in liquid-immersed contact, and margin-limitingmeans operative to confine positioning movement of said slide-holderplate to an extent that said optical means can never contact any part ofthe edge of the centrally open area of said plate.